The subject application relates generally to a header for use with agricultural harvesters. In particular, the subject application relates to an adjustable gathering chain assembly for an agricultural harvester header operable to harvest crops, such as corn.
The header of an agricultural harvester or combine is provided with row dividers and associated hoods for directing rows of corn stalks to downstream separation devices known as row units. The row units include stalk receiving slots and stripping plates, snapping rolls, and opposed rearwardly moving gathering chains. Thus, e.g., following separation of ears from stalks by the snapping rolls and stripping plates (also known as stalk rolls and deck plates, respectively), the separated ears are delivered by the gathering chains to an auger or other conveyor which conveys the harvested ears to a feederhouse of the combine. Harvested ears are then passed to the combine's inner chambers for downstream processing.
Row units are typically constructed with forwardly projecting members that support several components of the row unit including the deck plates, the stalk rolls, the gathering chains, the rear gathering chain sprockets (drive sprockets), the front gathering chain sprockets (driven sprockets), the hoods and the row dividers. Typical gathering chain assemblies include those in which the driven sprockets are located in a forwardly extended position relative to the leading edge of the deck plates and those where the driven sprockets are disposed in a somewhat retracted position relative to the leading edge of the deck plates. i.e., closer to the combine. Experience has shown that when the driven sprockets are situated in a prominently forward position relative to the deck plates, the header is better suited to gathering and lifting stalks of down or lodged crop. However, when the driven sprockets are situated in a forwardly projecting position, dry stalks tend to be knocked off by the gathering chain paddles before being engaged by the stalk rolls. Furthermore, when the driven sprockets are disposed in a relatively forwardly projecting position, the row units tend to pick up rocks and other debris which can cause clogging or even damage to the header. Conversely, when the driven sprockets are more rearwardly disposed relative to the deck plates, the row units are better suited to gathering crop that is more upright or standing because they knock off fewer standing stalks before they are pulled through the stalk rolls. However, no single location of the driven sprockets has been shown to be effective in harvesting under all crop conditions.
Accordingly, there is still a need for a row unit gathering chain assembly that addresses the foregoing issues associated with conventional headers. Such needs are satisfied by the subject application.